A smart card is typically a credit card-sized plastic card that includes a semiconductor chip capable of holding data supporting multiple applications.
Physically, a smart card often resembles a traditional "credit" card having one or more semiconductor devices attached to a module embedded in the card, providing contacts to the outside world. The card can interface with a point-of-sale terminal, an ATM, or a card reader integrated into a telephone, a computer, a vending machine, or any other appliance.
A micro-controller semiconductor device embedded in a "processor" smart card allows the card to undertake a range of computational operations, protected storage, encryption and decision making. Such a micro-controller typically includes a microprocessor, memory, and other functional hardware elements. Various types of cards are described in "The Advanced Card Report: Smart Card Primer", Kenneth R. Ayer and Joseph F. Schuler, The Schuler Consultancy, 1993.
One example of a smart card implemented as a processor card is illustrated in FIG. 1. Of course, a smart card may be implemented in many ways, and need not necessarily include a microprocessor or other features. The smart card may be programmed with various types of functionality, including applications such as stored-value; credit/debit; loyalty programs, etc.
In some embodiments, smart card 5 has an embedded micro-controller 10 that includes a microprocessor 12, random access memory (RAM) 14, read-only memory (ROM) 16, non-volatile memory 18, a cryptographic module 22, and a card reader interface 24. Other features of the micro-controller may be present but are not shown, such as a clock, a random number generator, interrupt control, control logic, a charge pump, power connections, and interface contacts that allow the card to communicate with the outside world.
Microprocessor 12 is any suitable central processing unit for executing commands and controlling the device. RAM 14 serves as storage for calculated results and as stack memory. ROM 16 stores the operating system, fixed data, standard routines, and look up tables. Non-volatile memory 18 (such as EPROM or EEPROM) serves t o store information that must not be lost when the card is disconnected from a power source but that must also be alterable to accommodate data specific to individual cards or any changes possible over the card lifetime. This information might include a card identification number, a personal identification number, authorization levels, cash balances, credit limits, etc. Cryptographic module 22 is an optional hardware module used for performing a variety of cryptographic algorithms. Card reader interface 24 includes the software and hardware necessary for communication with the outside world. A wide variety of interfaces are possible. By way of example, interface 24 may provide a contact interface, a close-coupled interface, a remote-coupled interface, or a variety of other interfaces. With a contact interface, signals from the micro-controller are routed to a number of metal contacts on the outside of the card which come in physical contact with similar contacts of a card reader device.
Various mechanical and electrical characteristics of smart card 5 and aspects of its interaction with a card reading device are defined by the following specifications, all of which are herein incorporated by reference.
Visa Integrated Circuit Card Specification, (Visa International Service Association 1996).
EMV Integrated Circuit Card Specification for Payment Systems, (Visa International Service Association 1996).
EMV Integrated Circuit Card Terminal Specification for Payment Systems, (Visa International Service Association 1996).
EMV Integrated Circuit Card Application Specification for Payment Systems, (Visa International Service Association 1996).
International Standard, Identification Cards--Integrated Circuit(s) Cards with Contacts, Parts 1-6 (International Standards Organization 1987-1995).
Prior to issuance of a smart card to a card user, the smart card is initialized such that some data is placed in the card. Initialization refers to the population of non-volatile memory with data that is common to a large number of cards while also including a minimal amount of card unique terms (e.g. card serial number and personalization keys). For example, during initialization, the smart card may be loaded with at least one application, such as credit or stored cash value, a file structure initialized with default values, and some initial cryptographic keys for transport security. Once a card is initialized, it is typically personalized. During personalization, the smart card is loaded with data which uniquely identifies the card. For example, the personalization data can include a maximum value of the card, a personal identification number (PIN), the currency in which the card is valid, the expiration date of the card, and cryptographic keys for the card.
A limitation of conventional smart cards is that new applications typically can not be added to an issued smart card. Smart cards are traditionally issued with one or more applications predefined and installed during the manufacturing process of the card. As a result, with traditional smart card implementation, once a card has been issued to a card user, the smart card becomes a fixed application card. If a new application is desired, the smart card is typically discarded and a new smart card, which includes the new application, is issued.
It would be desirable to provide a smart card which would allow applications to be loaded after the card is issued. Further, it is desirable to provide a mechanism to manage the loading of an application as well as general management of the applications on the smart card. Additionally, it is desirable to allow an application provider to keep cryptographic keys confidential from the issuer of the smart card and to securely allow applications from different entities to coexist on a card.